Project Summary Men continue to be missed by HIV testing and treatment services. Index partner testing is a critical strategy for reaching men. Index HIV self-testing (HIVST), whereby ART clients take HIVST kits home to their sexual partners for testing, is a new strategy that dramatically increases index testing among men, and is being taken to scale across Malawi. However, only 25% of men identified as HIV-positive through Index HIVST initiate ART after 6- months. Innovative strategies to increase ART initiation and retention among men are urgently needed. The overarching goal of the proposed R01 is to test a home-based ART intervention (ART initiation + 3-months ART care) plus motivational interviewing to increase ART initiation and 6-month viral suppression among men who test HIV-positive through Index HIVST in Malawi. The specific aims are: (1) test the effectiveness of home-based versus facility-based ART on ART initiation and 6-month viral suppression among male partners who test through Index HIVST; (2) Identify predictors of ART initiation and 6-month viral suppression; and (3) Determine the cost and cost-effectiveness of home-based ART versus facility-based among male partners using Index HIVST. The trial will provide urgent information on innovative HIV service delivery strategies for hard-to-reach-populations, such as men. Findings are expected to inform national policy and international recommendations around combined differentiated models that reach across the HIV treatment cascade.